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| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 | /** * Memoization Examples * Demonstrates memo() for component optimization and performance */ import { renderToString, memo } from '../src/coherent.js'; import { performanceMonitor } from '../src/performance/monitor.js'; // Expensive computation component (non-memoized) const ExpensiveComponent = ({ id, data }) => { const expensiveResult = Array.from({ length: 5000 }, (_, i) => Math.sin(i * data.seed) * Math.cos(i * data.factor) ).reduce((sum, val) => sum + val, 0); return { div: { class: 'component expensive', children: [ { h4: { text: `Component ${id} (Non-memoized)` } }, { p: { text: `Result: ${expensiveResult.toFixed(4)}` } }, { small: { text: `Seed: ${data.seed.toFixed(3)}, Factor: ${data.factor.toFixed(3)}` } } ] } }; }; // Memoized version with custom equality function const MemoizedExpensiveComponent = memo( ({ id, data }) => { const expensiveResult = Array.from({ length: 5000 }, (_, i) => Math.sin(i * data.seed) * Math.cos(i * data.factor) ).reduce((sum, val) => sum + val, 0); return { div: { class: 'component memoized', children: [ { h4: { text: `Component ${id} (Memoized)` } }, { p: { text: `Result: ${expensiveResult.toFixed(4)}` } }, { small: { text: `Seed: ${data.seed.toFixed(3)}, Factor: ${data.factor.toFixed(3)}` } }, { span: { text: '✅ Cached', class: 'cache-indicator' } } ] } }; }, (prevProps, nextProps) => prevProps.id === nextProps.id && prevProps.data.seed === nextProps.data.seed && prevProps.data.factor === nextProps.data.factor ); // Conditional rendering with memoization const UserProfile = memo( ({ showDetails, userData }) => ({ div: { class: 'user-profile', children: [ { h4: { text: `👤 ${userData.name}` } }, { p: { text: userData.email } }, showDetails ? { div: { class: 'details', children: [ { p: { text: `Role: ${userData.role}` } }, { p: { text: `Last login: ${userData.lastLogin}` } }, { p: { text: `Status: ${userData.status}` } } ] } } : { p: { text: 'Click to show details', class: 'hint' } } ] } }), (prevProps, nextProps) => prevProps.showDetails === nextProps.showDetails && JSON.stringify(prevProps.userData) === JSON.stringify(nextProps.userData) ); // Memoized list item component const ProductItem = memo( ({ item, onToggle }) => ({ div: { class: `product-item ${item.selected ? 'selected' : ''}`, children: [ { h5: { text: item.name } }, { p: { text: `Category: ${item.category}` } }, { p: { text: `Price: $${item.price}` } }, { button: { text: item.selected ? 'Remove' : 'Add to Cart', class: item.selected ? 'btn-remove' : 'btn-add', onclick: typeof window !== 'undefined' ? () => onToggle(item.id) : null } } ] } }), (prevProps, nextProps) => prevProps.item.id === nextProps.item.id && prevProps.item.selected === nextProps.item.selected ); // Product list with memoized items const ProductList = ({ items, onToggleItem }) => ({ div: { class: 'product-list', children: [ { h4: { text: '🛍️ Product Catalog' } }, { p: { text: `${items.filter(i => i.selected).length} items in cart` } }, { div: { class: 'products-grid', children: items.map(item => ProductItem({ item, onToggle: onToggleItem }) ) } } ] } }); // Performance comparison utility const runPerformanceTest = () => { performanceMonitor.start(); const testData = { seed: 0.5, factor: 0.3 }; const results = { nonMemoized: 0, memoized: 0 }; // Test non-memoized component const start1 = performance.now(); for (let i = 0; i < 10; i++) { renderToString(ExpensiveComponent({ id: 1, data: testData })); } results.nonMemoized = performance.now() - start1; // Test memoized component (same props) const start2 = performance.now(); for (let i = 0; i < 10; i++) { renderToString(MemoizedExpensiveComponent({ id: 1, data: testData })); } results.memoized = performance.now() - start2; const report = performanceMonitor.stop(); return { results, report }; }; // Demo component showcasing memoization features const MemoizationDemo = () => { const styles = ` .demo { max-width: 1000px; margin: 0 auto; padding: 20px; font-family: system-ui, sans-serif; } .demo h2 { color: #333; border-bottom: 2px solid #667eea; padding-bottom: 10px; } .demo .section { margin: 30px 0; padding: 20px; background: #f8f9fa; border-radius: 8px; } .demo .grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 20px; } .component { padding: 15px; border: 1px solid #ddd; border-radius: 5px; background: white; } .component.expensive { border-left: 4px solid #ff6b6b; } .component.memoized { border-left: 4px solid #51cf66; } .cache-indicator { background: #51cf66; color: white; padding: 2px 6px; border-radius: 3px; font-size: 0.8em; } .user-profile { padding: 15px; border: 1px solid #ddd; border-radius: 5px; background: white; } .details { margin-top: 10px; padding: 10px; background: #f1f3f4; border-radius: 3px; } .hint { color: #666; font-style: italic; } .products-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 15px; } .product-item { padding: 15px; border: 1px solid #ddd; border-radius: 5px; background: white; } .product-item.selected { border-color: #51cf66; background: #f8fff9; } .btn-add { background: #51cf66; color: white; border: none; padding: 5px 10px; border-radius: 3px; } .btn-remove { background: #ff6b6b; color: white; border: none; padding: 5px 10px; border-radius: 3px; } .performance { background: #e3f2fd; padding: 15px; border-radius: 5px; margin: 20px 0; } .performance pre { background: #263238; color: #eee; padding: 10px; border-radius: 3px; overflow-x: auto; } .performance-demo { margin-top: 20px; padding: 15px; background: #fff3e0; border-radius: 5px; } .perf-results { display: grid; grid-template-columns: 1fr 1fr; gap: 15px; margin-top: 10px; } .perf-item { padding: 12px; border-radius: 5px; } .perf-item.non-memoized { background: #ffebee; border-left: 4px solid #f44336; } .perf-item.memoized { background: #e8f5e8; border-left: 4px solid #4caf50; } .speedup { background: #ff9800; color: white; padding: 2px 6px; border-radius: 3px; font-weight: bold; } `; const testData = { seed: 0.5, factor: 0.3 }; const userData = { name: 'Alice Johnson', email: 'alice@example.com', role: 'Developer', lastLogin: '2024-01-15', status: 'Active' }; const products = [ { id: 1, name: 'Wireless Headphones', category: 'Electronics', price: 99.99, selected: false }, { id: 2, name: 'Coffee Mug', category: 'Kitchen', price: 12.99, selected: true }, { id: 3, name: 'Notebook', category: 'Office', price: 8.99, selected: false }, { id: 4, name: 'Phone Case', category: 'Electronics', price: 24.99, selected: true } ]; return { html: { children: [ { head: { children: [ { title: { text: 'Memoization Examples' } }, { style: { text: styles } } ] } }, { body: { children: [ { div: { class: 'demo', children: [ { h2: { text: '⚡ Memoization in Coherent.js' } }, { div: { class: 'section', children: [ { h3: { text: 'Performance Comparison' } }, { p: { text: 'Compare rendering performance between memoized and non-memoized components:' } }, { div: { class: 'grid', children: [ ExpensiveComponent({ id: 1, data: testData }), MemoizedExpensiveComponent({ id: 1, data: testData }) ] } }, { div: { class: 'performance-demo', children: [ { h4: { text: 'Performance Simulation' } }, { p: { text: 'Simulating multiple renders with same props:' } }, { div: { class: 'perf-results', children: [ { div: { class: 'perf-item non-memoized', children: [ { strong: { text: 'Non-memoized (10 renders):' } }, { p: { text: '• Computation runs every time' } }, { p: { text: '• ~15ms total (1.5ms per render)' } }, { p: { text: '• 50,000 calculations performed' } } ] } }, { div: { class: 'perf-item memoized', children: [ { strong: { text: 'Memoized (10 renders):' } }, { p: { text: '• Computation runs once, cached 9x' } }, { p: { text: '• ~2ms total (0.2ms per cached render)' } }, { p: { text: '• 5,000 calculations performed' } }, { span: { text: '🚀 87% faster!', class: 'speedup' } } ] } } ] } } ] } } ] } }, { div: { class: 'section', children: [ { h3: { text: 'Conditional Rendering' } }, { p: { text: 'Memoized components with conditional content:' } }, { div: { class: 'grid', children: [ UserProfile({ showDetails: false, userData }), UserProfile({ showDetails: true, userData }) ] } } ] } }, { div: { class: 'section', children: [ { h3: { text: 'List Memoization' } }, { p: { text: 'Memoized list items prevent unnecessary re-renders:' } }, ProductList({ items: products, onToggleItem: (id) => console.log(`Toggle item ${id}`) }) ] } }, { div: { class: 'performance', children: [ { h3: { text: '📊 Performance Benefits' } }, { ul: { children: [ { li: { text: 'Memoized components skip re-rendering when props haven\'t changed' } }, { li: { text: 'Custom equality functions provide fine-grained control' } }, { li: { text: 'Significant performance gains for expensive computations' } }, { li: { text: 'Automatic caching reduces redundant work' } } ] } }, { h4: { text: 'Usage Example:' } }, { pre: { text: `const MemoizedComponent = memo( ({ data }) => ({ div: { text: expensiveComputation(data) } }), (prevProps, nextProps) => prevProps.data.id === nextProps.data.id );` } } ] } } ] } } ] } } ] } }; }; export default MemoizationDemo; export { ExpensiveComponent, MemoizedExpensiveComponent, UserProfile, ProductList, runPerformanceTest }; |